Just 6 percent of respondents said they were undecided on who to vote for despite the fact it was more than five months before Election Day.

DeMaio also had a slight edge over Peters when respondents were asked who was more trustworthy with 45 percent giving the nod to him compared to 41 percent for Peters.

The poll, conducted by SurveyUSA on Wednesday and Thursday, found that DeMaio had a 17-point lead over Peters among men.

Peters held a 2-point edge over DeMaio among women respondents in the survey taken a week after the June 3 primary that saw two other Republican challengers for 52nd Congressional District seat, Kirk Jorgensen and Fred Simon, eliminated from the race.

SurveyUSA founder and editor Jay Leve said it’s too early to make any conclusive judgment about the nationally watched match-up.

“Scott Peters is the underdog at this point, but there is nothing in these numbers to suggest that this race is in any way a forgone conclusion,” Leve said. “Six months of campaigning are just getting started and anything can happen.”

The poll has a margin of error of plus or minus 4.2 percent,

Among independents, DeMaio had big lead over Peters, topping the former San Diego City Council president and port commissioner by 20 points at 57 percent to 37 percent. That group makes up nearly a third of the district’s 385,540 registered voters.

The Peters-DeMaio election is targeted by the national Republican and Democratic parties in part because of the swing nature of the district drawn in 2010 following the latest census. Democrats make up 32.2 percent of the registrants compared with 33.7 percent Republicans.

While DeMaio was winning independents, Peters led among self-described moderates at 54 percent to 43 percent.

“This is the group that DeMaio really needs to watch because they can largely influence who is the winner,” Leve said.

Both men appear in solid shape with their core supporters, according to the poll. DeMaio is favored by 82 percent Republicans and 88 percent of self-described conservatives. Peters is backed by 85 percent of Democratic voters and 87 percent of self-described liberals.

DeMaio, also a former San Diego City Councilman, and 2012 mayoral candidate, is one of a handful of openly gay Republicans running for Congress this year and was one of the first to air an ad featuring his partner.

The survey found his sexual orientation is of no concern with the vast majority of voters. Nearly nine of every 10 respondents said it was not a factor in their decision on which candidate they were supporting.

Jorgensen captured more than 18 percent of the primary vote, running on a social conservative platform that included opposition to same-sex marriage and abortion. Seven out of 10 voters who went with him in the primary now say that DeMaio will get their vote, according to the poll.

“Both the Jorgensen voters and the independents have broken Republican in a significant way,” Leve said.

Thirteen percent of Jorgensen voters said they would vote for Peters; 17 percent were undecided.

DeMaio led Peters among white voters at 52 percent to 43 percent. Peters was ahead in the Latino vote with 54 percent to 43 percent for DeMaio.

Among Asians and voters of other ethnic groups, DeMaio had an eight-point advantage with 16 percent of those respondents saying they were undecided.

Asked what was the leading characteristic they want to see in their congressman, 36 percent of respondents said integrity, 20 percent cited ability to reach across party lines and 18 percent said fiscal responsibility.

Asked to choose from a list of the most important challenges they see facing the country, 36 percent said unemployment compared with 15 percent who cited taxation. Twelve percent said education and 11 percent said climate change.

The poll’s key result showing DeMaio in the lead against Peters is comparable to one conducted by SurveyUSA in June 2013 that found him ahead by 10 percent.

Peters got 42.2 percent of the vote in the June 3 primary while DeMaio pocketed 35.2 percent. The two enter the general election season with more than $1 million in each of their campaign accounts.